Technical skill, a good sense of melody, and cyclical song structure with variation between songs. If it doesn't have these then it's not metal. That's why I don't consider a lot of 'modern metal' to be actual metal to because it doesn't have any of these elements.
Anything that is categorized as metal. Just because a certain sub genre isn't to your liking doesn't mean it isn't metal. I'm not keen on metal where the lead singer constantly screams and can't be understood, but I don't go on about how it shouldn't be considered metal.
Slayer Pantera Iron Maiden Megadeth Motorhead Black Sabbath Judas Priest Anthrax Motley Crue Alice in Chains (Mostly grunge, but it's pretty heavy Sludge Metal, too)
Just about all of it is metal, technically. We just wanna make a distinction between what metal fans actually listen to, and the teen pop bullshlt metal. There does not exist those metal fans you're talking about, who think singing doesn't belong in metal, they're all trolls, I never met a person in the real world who thought that way. Nobody says power metal isn't metal, nobody says symphonic metal isn't metal, long standing genre's like these have earned their place.
Thrash Metal Death Metal Black Metal And all sub variations of those genres I do consider all metal to be metal, but if I say REAL metal I mean the stuff that displays extreme skills and aggression Example : Bullet for my valentine or Asking Alexandria are technically metal bands, but Megadeth or Cannibal Corpse are REAL metal bands
